are only a few companies in the UK specialising in providing specialised
surveys and mapping photography. Some provide pipeline, coastal,
environmental and surface terrain surveys, others specialise in
geophysical site investigations and sub-surface mapping. Between
them, however, they offer a wide range of technical services and
expertise, including, geo-referenced aerial photography, Global
Positioning Systems (GPS), Photogrammetry, Geographic Information
Systems (GIS), Digital Orthoimagery & LiDAR
surveys are routinely employed in site investigations, as they are
the only non-invasive method of identifying the nature of the features
that lie below the subsurface. Applications include investigations
into oil and mineral deposits, groundwater, archaeological, civil
engineering, geological and environmental projects.
Aerial photography - Successful mapping projects begin with
precise aerial photography. Using the most accurate image capture
equipment available is essential for best results. Certain specialised
cameras, considered the most accurate aerial cameras available,
incorporate the latest technology such as forward motion compensation,
automatic crab compensation and a gyroscopic stabilization mount
system. These cameras are compatible with in-plane photo-control
GPS (where reaching pre-determined GPS coordinates, they trigger
shutter actuation) and utilise either or both terrain-based and
GPS control points for precision geo-referenced photography.
Global Positioning System - GPS uses intersecting transmitted
signals from orbiting geostationary satellites to accurately pinpoint
locations on earth, and was devised for military navigation and
targeting systems. Today,
it forms the basis of many civilian and commercial applications
including the determination of coordinates of natural features and
man-made objects for mapping and GIS databases.
- A photogrammetric mapping service uses a compilation of stereo
images to produce accurate digital models and site plans.
Following an aerial photography survey of a site, digital images
are downloaded to a computer where modelling software can produce
the resultant model very rapidly.
Information Systems - GIS combines a number of different sources
of geographical and topographic information and incorporates them
into a layered database that can be interrogated and analysed in
a variety of ways. This newly available tool is a sophisticated
and spatially-referenced database able to be accessed by users for
an almost limitless number of applications.
Orthoimagery - DOI combines mapping information with its photographic
image. The accuracy of photogrammetrically-scaled maps, GIS and
the large amount of inherent information within aerial and satellite
imagery provides a vast technical and scientific resource for both
commercial and academic users. It can be used for constructing aligning
overlays of geographical features such as natural resources and
other features not visible on an ordinary, un-enhanced photograph.
- Light Detection And Ranging is an airborne remote sensing technique
able to record millions of 3-D geo-referenced points on a single
survey mission. Using a pulsed laser beam, which is scanned from
side to side as the aircraft passes over the survey site, it can
measure up to 100,000 points per second. Specially adapted helicopters
or fixed-wing aircraft can be used and typically, surveys are flown
at about 1,000 metres and can collect data over a width of terrain
up to 700m wide or a narrow cone for engineering corridors such
as transmission and pipelines and road and rail tracks. Simultaneous
image and terrain capture on the same pass speeds up processing
and mapping, providing an accurate and cost-efficient method of
3-D terrain modelling for clients.
- With the aid of modern mapping techniques and software, it is
now possible to 'stitch' together large numbers of individual high-resolution
photographs (taken as a pre-planned series of survey shots) to form
a single, seamless image. Mosaics can therefore show large areas
of terrain or towns in accurate, precise detail, not possible a
short while ago.
We are able to identify the most appropriate company
the specialist services you require.
contact Ron Bridle on 07789 871620
or e-mail via the Contact page.